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computer ?

  • Thread starter Thread starter keithnra
  • Start date Start date May 26, 2006

keithnra

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Apr 30, 2006
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May 26, 2006
#1
  • May 26, 2006
  • #1
If I am going to change my 89 LX from an Automatic to a 5 speed will I need another computer. Also what all will I need to get. I have bellhousing, shifter, pedals, and I think that is it.
 

83Mustang427TT

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Jan 18, 2006
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May 26, 2006
#2
  • May 26, 2006
  • #2
You need an A9L computer the auto puter doesnt have the fuel curves that the manual one has and I have heard it may cause a no start problem and also wont have the rpms to shift when you need to..
 

jrichker

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#3
  • May 26, 2006
  • #3
I have personally run both the A9L (5speed) & A9P (auto) on a 5 speed car. Both computers will work with no problems.
 

83Mustang427TT

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#4
  • May 26, 2006
  • #4
I have heard that you can run the auto but it has a much lower rev limit then the A9L think I read it on www.fordfuelinjection.com also when coming to a stop the auto computer by way of a pip signal trys to stall the car out when in a manual equipped car...I could very well be wrong but Im in the process of swapping a 351W C-4 combo into a 4 banger and have done alot of research on the computer functions and which one to use A9P does have better fuel and spark tables but like I said there are some differences
 

wht93gtEd

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May 26, 2006
#5
  • May 26, 2006
  • #5
jrichker said:
I have personally run both the A9L (5speed) & A9P (auto) on a 5 speed car. Both computers will work with no problems.
Click to expand...

But can't you only do this if the car was originally a 5spd? I know you can't run a 5spd computer in a car that was originally an AOD because of the whole pin30 thing with the NSS; but I think you can run an AOD computer in an original 5spd car?

To answer the original questioh, no, you don't have to change the computer.

83Mustang427TT said:
have heard that you can run the auto but it has a much lower rev limit then the A9L think I read it on www.fordfuelinjection.com also when coming to a stop the auto computer by way of a pip signal trys to stall the car out when in a manual equipped car...I could very well be wrong but Im in the process of swapping a 351W C-4 combo into a 4 banger and have .
Click to expand...

you're right and wrong...
lower rev limiter = yes
stalling when stopping = no

It's been almost 2 years and 40k miles since I swapped my car from AOD to 5spd and it's never once stalled or almost stalled for that matter when comming to a stop. As a matter of fact it just perfect...just like a factory 5spd car would.
 

HISSIN50

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#6
  • May 26, 2006
  • #6
In case it factors in (regarding post 2), another source of confusion if searching is that the AOD(E) computer (U4) will cause a bogging while driving along after a swap because that computer controls shifts electronically. It will hiccup when it knows it was supposed to shift. None of that should apply to the TV actuated tranny/computers.
 

keithnra

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Apr 30, 2006
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May 29, 2006
#7
  • May 29, 2006
  • #7
will an A9L computer out of a 92 GT work in a 89 LX if i am trying to change over from auto-5 spd. will the wiring harness wire right up with no problems. I guess my question is are all A9L computers the same 87-93?
 

GearHd6

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May 29, 2006
#8
  • May 29, 2006
  • #8
You'll have no problems with the AOD computer when you do the 5 speed swap. I've done it with no problems. One thing that has to be done is the neutral safety switch HAS to be bypassed or you'll have a high idle condition as soon as you put the car in any gear other than neutral. The reason being is with the AOD, when its put in gear just from the drag from the converter its trying to drop the RPM's so the computer compensates by increasing the RPM's by a couple hundred.
 
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